Configurable encoder for cyclic error correction codes

• US 8,595,602 B2
• Filed: 06/18/2013
• Issued: 11/26/2013
• Est. Priority Date: 11/14/2008
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Anholt, Micha
• Primary Examiner(s): Ehne, Charles
• Application Number:
  US13/920,157
• Publication Number:
  US 20130272356A1
• Time in Patent Office: 161 Days
• Field of Search: 714/781
• US Class Current: 714/781
• CPC Class Codes: H03M 13/1515 Reed-Solomon codes
• CPC Class Codes: H03M 13/152 Bose-Chaudhuri-Hocquenghem [BCH] codes
• CPC Class Codes: H03M 13/159 Remainder calculation, e.g. for encoding and syndrome calculation
• CPC Class Codes: H03M 13/6516 Support of multiple code parameters, e.g. generalized Reed-Solomon decoder for a variety of generator polynomials or Galois fields
• CPC Class Codes: H04L 1/004 by using forward error control H04L1/0618 takes precedence; coding, decoding or code conversion, for error detection or correction H03M13/00
• CPC Class Codes: H04L 1/0041 Arrangements at the transmitter end

Abstract

Apparatus for encoding includes a first processing stage, which is configured to filter input data with a first set of coefficients belonging to a first generator polynomial representing a first ECC, to produce a first output. A second processing stage is configured to filter the first output using a second set of coefficients belonging to a quotient polynomial, which is defined as a quotient of a second generator polynomial, representing a second ECC, divided by the first generator polynomial, to produce a second output. Ancillary circuitry has first and second operational modes and is coupled to the first and second processing stages so as to generate a first redundancy output corresponding to the first ECC based on the first output when operating in the first mode, and to generate a second redundancy output corresponding to the second ECC based on the second output when operating in the second mode.

Claims

1. An mobile communication device, comprising:

an Error Correction Code (ECC) encoder configured to receive input data, and encode the received input data with an ECC;

a modem coupled to the ECC encoder, wherein the modem is configured to modulate the encoded data; and

a front-end unit coupled to the modem, wherein the front-end unit is configured to;

convert the modulate encoded data into an analog signal;

convert the analog signal into a radio frequency (RF) signal; and

transmit the RF signal to a receiver using an antenna;

wherein to encode the received input data, the ECC encoder is further configured to;

filter the received input data using a first set of coefficients to produce a first output; and

filter the first output using a second set of coefficients.

2. The apparatus of claim 1, wherein the first set of coefficients belong to a first generator polynomial representing a first ECC code.

3. The apparatus of claim 2, wherein the second set of coefficients belong to a quotient polynomial, wherein the quotient polynomial is a second generator polynomial representing a second ECC code divided by the first generator polynomial.

4. The apparatus of claim 2, wherein the ECC encoder is further configured to modify at least one of the coefficients.

5. The apparatus of claim 2, wherein the ECC encoder is further configured to generate a first redundancy output by calculating a bit-wise exclusive-OR (XOR) between the input data and the first generator polynomial.

6. The apparatus of claim 5, wherein to encode the input data, the ECC encoded is further configured to generate a second redundancy output by calculating a bit-wise XOR between the input data and the second output.

7. The apparatus of claim 6, wherein to encode the input data, the ECC encoder is further configured to select the first redundancy output of the second redundancy output dependent upon an operational mode.

8. A method, comprising:

receiving input data;

filtering the received input data using a first set of coefficients to produce a first output;

filtering the first output using a second set of coefficients;

generating an encoded output dependent upon the first output and the second output;

modulating the encoded output;

converting the modulated selected output into an analog signal;

converting the analog signal into a radio frequency (RF) signal; and

transmitting the RF signal to a receiver using an antenna.

9. The method of claim 8, wherein the first set of coefficients belong to a first generator polynomial representing a first ECC code and the second set of coefficients belong to a quotient polynomial, wherein the quotient polynomial is a second generator polynomial representing a second ECC code divided by the first generator polynomial.

10. The method of claim 9, wherein generating the encoded output comprises, generating a first redundancy output by calculating a bit-wise exclusive-OR (XOR) between the input data and the first generator polynomial.

11. The method of claim 10, wherein generating the encoded output further comprises, generating a second redundancy output by calculating a bit-wise XOR between the input data and the second output.

12. The method of claim 11, wherein generating the encoded output further comprises selecting the first redundancy output or the second redundancy output dependent upon an operational mode.

13. The method of claim 8, further comprising modifying at least one of the first set of coefficients or the second set of coefficients.

14. The method of claim 8, further comprising modifying one of the first and second set of coefficients, wherein the other of the first and second set of coefficients is fixed.

15. A computer-accessible non-transitory storage medium, having program instructions stored therein that, in response to execution by a computer system, cause the computer system to perform operations including:

receiving input data;

filtering the received input data using a first set of coefficients to produce a first output;

filtering the first output using a second set of coefficients;

generating an encoded output dependent upon the first output and the second output;

modulating the encoded output;

converting the modulated selected output into an analog signal;

converting the analog signal into a radio frequency (RF) signal; and

transmitting the RF signal to a receiver using an antenna.

16. The computer-accessible non-transitory storage medium of claim 15, wherein to perform operations further includes modifying one of the first and second set of coefficients, wherein the other of the first and second set of coefficients is fixed.

17. The computer-accessible non-transitory storage medium of claim 15, wherein the first set of coefficients belong to a first generator polynomial representing a first ECC code and the second set of coefficients belong to a quotient polynomial, wherein the quotient polynomial is a second generator polynomial representing a second ECC code divided by the first generator polynomial.

18. The computer-accessible non-transitory storage medium of claim 17, wherein the first ECC code has a first maximum number of correctable errors, and the second ECC code has a second maximum number of correctable errors, wherein the second maximum number of correctable errors is larger than the first maximum number of correctable errors.

19. The computer-accessible non-transitory storage medium of claim 15, wherein the first ECC code comprises a first Bose-Chaudhuri-Hocquenghem (BCH) code, and wherein the second ECC code comprises a second BCH code.

20. The computer-accessible non-transitory storage medium of claim 15, wherein generating the encoded output comprises:

generating a first redundancy output by calculating a bit-wise exclusive-OR (XOR) between the input data and the first generator polynomial;

generating a second redundancy output by calculating a bit-wise XOR between the input data and the second output; and

selecting the first redundancy output or the second redundancy output dependent upon an operational mode.